etcd3 image based on Alpine Linux
docker run -d -p 2379:2379 -p 2380:2380 appcelerator/etcd
You can set the listen URLs for clients and peers:
docker run -d -p 2379:2379 -p 2380:2380 appcelerator/etcd --listen-client-urls http://localhost:2379 --advertise-client-urls http://localhost:2379 --listen-peer-urls=http://localhost:2380 --initial-advertise-peer-urls=http://localhost:2380
to run an etcd cluster with Docker swarm, you have to specify the name of the service, and optionally the minimum number of seeds for the cluster to be created.
docker network create --driver overlay db
docker service create --network db -e SERVICE_NAME=etcd -e MIN_SEEDS_COUNT=3 --replicas 3 --name etcd appcelerator/etcd
or use the sample stack file from this repository:
docker stack deploy -c ./etcd.yml etcd
In case something goes wrong and the etcd is broken (quorum is lost), there's still a way to fix it if you have a snapshot of the DB.
Prepare the backup file, and make sure the volume mount in etcd-restore.yml is correct.
Remove the existing cluster, we'll start from fresh.
$ docker stack deploy -c etcd-restore.yml backup
This will create a new cluster with the backuped data. Now we can create the permanent cluster:
$ docker stack deploy -c etcd.yml etcd
give it time to stabilize, and remove the temporary members:
$ docker run --rm -ti --network etcd appcelerator/etcd:lastest /bin/bash
bash-4.4# etcdctl --endpoints etcd:2379 member list
15e2efb88226a3da, started, etcd-13, http://10.0.2.13:2380, http://10.0.2.13:2379,http://10.0.2.13:4001
6890ef829475b2cd, started, etcdrestore-6, http://10.0.2.6:2380, http://etcd:2379
734d10a4021f8332, started, etcdrestore-5, http://10.0.2.5:2380, http://etcd:2379
b8ecbd5bfd457170, started, etcd-10, http://10.0.2.10:2380, http://10.0.2.10:2379,http://10.0.2.10:4001
eec3f10e2dfadc0e, started, etcd-14, http://10.0.2.14:2380, http://10.0.2.14:2379,http://10.0.2.14:4001
fd2519db4a9702be, started, etcdrestore-4, http://10.0.2.4:2380, http://etcd:2379
bash-4.4# etcdctl --endpoints etcd:2379 member remove 6890ef829475b2cd
Member 6890ef829475b2cd removed from cluster a12d20375028bb05
bash-4.4# etcdctl --endpoints etcd:2379 member remove 734d10a4021f8332
Member 734d10a4021f8332 removed from cluster a12d20375028bb05
bash-4.4# etcdctl --endpoints etcd:2379 member remove fd2519db4a9702be
Member fd2519db4a9702be removed from cluster a12d20375028bb05
bash-4.4# etcdctl --endpoints etcd:2379 member list
15e2efb88226a3da, started, etcd-13, http://10.0.2.13:2380, http://10.0.2.13:2379,http://10.0.2.13:4001
b8ecbd5bfd457170, started, etcd-10, http://10.0.2.10:2380, http://10.0.2.10:2379,http://10.0.2.10:4001
eec3f10e2dfadc0e, started, etcd-14, http://10.0.2.14:2380, http://10.0.2.14:2379,http://10.0.2.14:4001
bash-4.4# etcdctl --endpoints etcd:2379 endpoint health
etcd:2379 is healthy: successfully committed proposal: took = 1.869464ms
exit
$ docker stack rm backup
- 3.0, 3.0.15
- 3.1, 3.1.11
- 3.2, 3.2.16
- 3.3, 3.3.1, latest